Siemens SIMATIC HMI Operating Instructions Manual page 103

Operation
Undesirable enabling function
Only push the enabling button until the operation which you enabled has been completed.
The enabling function is an intentional operator action. It is not permissible to constantly
hold the enabling button or lock it otherwise.
If you leave the effective range only briefly for a time period of up to 30 seconds while the
enabling button is pressed, the following occurs: 5 seconds after you have left the effective
range, the enabling function is revoked. If you return to the effective range within 30
seconds with the enabling button still pressed, the enabling function is automatically
returned.
The enabling button has three switch settings:
● Neutral position: The enabling button is not pressed.
● Enable: The enabling button is pressed to a mid position. This switch setting is used to
● Panic: The switch setting "Panic" is achieved as soon as one of the enabling buttons
You only have to activate one enabling button. The PLC receives the same signal regardless
of whether only one or both enabling buttons of the Mobile Panel 277F IWLAN having been
pushed.
Note
The enabling button and the membrane keyboard can be operated at the same time.
When using the enabling button the following F-FBs must be linked in the safety program of
the F CPU:
● F_FB_MP
● F_FB_RNG_n
Switch settings
The following figure shows the switching sequence for enable.
Mobile Panel 277F IWLAN
Operating Instructions, 12/2007, A5E01003940-01
WARNING
allow another command, for example an input with the membrane keyboard.
have been pressed. The switch setting of the other enabling button is irrelevant in this
case. The switch setting "Panic" has the same effect as releasing the enabling button,
namely revoking the enable.
Operator controls and displays
5.4 Safety-related operator controls
103